Battery packs have been known that accommodate battery cells in a sealed case. In a battery pack, the internal pressure of the sealed case must be lowered when the internal pressure is high.
Patent Document 1 discloses a battery module that accommodates rechargeable batteries in a housing. A gas discharging member, which is opened at a preset pressure, is attached to each rechargeable battery. The housing has a gas discharging hole and a valve member, which closes the gas discharging hole. In the battery module, the valve member is opened when the internal pressure of the housing reaches a preset pressure.
Typically, a cable is attached to the battery pack to connect the battery pack to an external device. In the configuration of Patent Document 1, opening the valve member may cause gas to be discharged from the housing toward the cable. This may damage the cable and thus hamper charging/discharging of the battery pack.